結果

問題 No.599 回文かい
コンテスト
ユーザー はまやんはまやん
提出日時 2017-11-24 23:48:00
言語 C++14
(gcc 13.3.0 + boost 1.87.0)
結果
WA  
実行時間 -
コード長 8,459 bytes
コンパイル時間 2,423 ms
コンパイル使用メモリ 180,880 KB
実行使用メモリ 6,824 KB
最終ジャッジ日時 2024-11-27 08:33:09
合計ジャッジ時間 3,160 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge3
このコードへのチャレンジ
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ファイルパターン 結果
other AC * 4 WA * 18
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ソースコード

diff # 

#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)
#define fore(i,a) for(auto &i:a)
#pragma GCC optimize ("-O3")
using namespace std; void _main(); int main() { cin.tie(0); ios::sync_with_stdio(false); _main(); }
//---------------------------------------------------------------------------------------------------
template<int MOD> struct ModInt {
    static const int Mod = MOD; unsigned x; ModInt() : x(0) { }
    ModInt(signed sig) { x = sig < 0 ? sig % MOD + MOD : sig % MOD; }
    ModInt(signed long long sig) { x = sig < 0 ? sig % MOD + MOD : sig % MOD; }
    int get() const { return (int)x; }
    ModInt &operator+=(ModInt that) { if ((x += that.x) >= MOD) x -= MOD; return *this; }
    ModInt &operator-=(ModInt that) { if ((x += MOD - that.x) >= MOD) x -= MOD; return *this; }
    ModInt &operator*=(ModInt that) { x = (unsigned long long)x * that.x % MOD; return *this; }
    ModInt &operator/=(ModInt that) { return *this *= that.inverse(); }
    ModInt operator+(ModInt that) const { return ModInt(*this) += that; }
    ModInt operator-(ModInt that) const { return ModInt(*this) -= that; }
    ModInt operator*(ModInt that) const { return ModInt(*this) *= that; }
    ModInt operator/(ModInt that) const { return ModInt(*this) /= that; }
    ModInt inverse() const { long long a = x, b = MOD, u = 1, v = 0;
        while (b) { long long t = a / b; a -= t * b; std::swap(a, b); u -= t * v; std::swap(u, v); }
        return ModInt(u); }
    bool operator==(ModInt that) const { return x == that.x; }
    bool operator!=(ModInt that) const { return x != that.x; }
    ModInt operator-() const { ModInt t; t.x = x == 0 ? 0 : Mod - x; return t; }
};
template<int MOD> ostream& operator<<(ostream& st, const ModInt<MOD> a) { st << a.get(); return st; };
template<int MOD> ModInt<MOD> operator^(ModInt<MOD> a, unsigned long long k) {
    ModInt<MOD> r = 1; while (k) { if (k & 1) r *= a; a *= a; k >>= 1; } return r; }
typedef ModInt<1000000007> mint;
#ifdef _MSC_VER
inline unsigned int __builtin_clz(unsigned int x){unsigned long r;_BitScanReverse(&r,x);return 31-r;}
inline int __lg(int __n) { return sizeof(int) * 8 - 1 - __builtin_clz(__n); }
#endif
template<class T> struct IRMQ {
    int n; T *d;
    IRMQ() : n(0), d(NULL) {}
    template<class Iter> IRMQ(Iter begin, Iter end) : n(0), d(0) { build(begin, end); }
    IRMQ(const IRMQ &y) : n(y.n), d(NULL) { if (y.n) build(y.d[0], y.d[0] + n); }
    IRMQ(IRMQ &&y) : n(0), d(NULL) { swap(*this, y); }
    ~IRMQ() { if (n) { n = 0; delete d; d = NULL; } }
    friend void swap(IRMQ &x, IRMQ &y) { swap(x.n, y.n); swap(x.d, y.d); }
    IRMQ& operator=(IRMQ y) { swap(*this, y); return *this; }

    template<class Iter> void build(Iter begin, Iter end) { // random access iterator
        n = end - begin;
        if (n == 0) return;
        int g = __lg(n);
        d = new T[n*(g + 1)];
        rep(i, 0, n) { d[i] = *begin; ++begin; }
        for (int t = 0, b = 0; t<g; t++, b += n) for (int i = 0, j = 1 << t; j <= n - (1 << t); i++, j++)
            d[b + n + i] = (d[b + j] < d[b + i] ? d[b + j] : d[b + i]);
    }

    const T at(int i) const { return d[i]; }

    const T min_v(int l, int r) const {
        int g = __lg(r - l), b = n * g;
        r -= 1 << g;
        return d[b + r] < d[b + l] ? d[b + r] : d[b + l];
    }

    int min_i(int l, int r) const {
        return next_less_equal(l, min_v(l, r));
    }

};

class SAIS {
public:
    vector<int> sa, lcp, rank;
    SAIS() {}
    SAIS(const string &str_) {
        N = str.size() + 1;
        S = vector<int>(N, 0);
        for (int i = 0; i<N; i++) S[i] = str[i];
        *this = SAIS(S, 256);
    }
    SAIS(const vector<int> &S_, int A_SIZE_, bool lcp_flag = true) : S(S_), A_SIZE(A_SIZE_) {
        buildSA();
        if (lcp_flag) buildLCP();
    }
    void init(const string &str_) {
        str = str_;
        N = str.size() + 1;
        S = vector<int>(N, 0);
        for (int i = 0; i<N; i++) S[i] = str[i];
        A_SIZE = 256;
        buildSA();
        buildLCP();
    }
private:
    string str;
    vector<int> S;
    int A_SIZE;
    int N;
    vector<int> t, B;
    enum { STYPE, LTYPE };

    inline bool is_lms(int i) {
        return i>0 && t[i] == STYPE && t[i - 1] == LTYPE;
    }
    void bucket() {
        B = vector<int>(A_SIZE);
        for (int i = 0; i<N; i++) B[S[i]]++;
        for (int i = 0; i<A_SIZE - 1; i++) B[i + 1] += B[i];
    }
    void induced_sort() {
        bucket();
        for (int i = 0; i<N; i++) {
            int j = sa[i] - 1;
            if (j >= 0 && S[j] >= S[j + 1]) sa[B[S[j] - 1]++] = j;
        }
        bucket();
        for (int i = N; i--; ) {
            int j = sa[i] - 1;
            if (j >= 0 && S[j] <= S[j + 1]) sa[--B[S[j]]] = j;
        }
    }
    void buildSA() {
        N = S.size();
        sa.assign(N, -1);
        if (N == 1) {
            sa[0] = 0;
            return;
        }
        t.assign(N, STYPE);
        for (int i = N - 1; i--;)
            if (S[i] > S[i + 1] || (S[i] == S[i + 1] && t[i + 1] == LTYPE))
                t[i] = LTYPE;
        bucket();
        for (int i = N; i--;)
            if (is_lms(i)) sa[--B[S[i]]] = i;
        induced_sort();

        int N1 = 0;
        for (int i = 0; i<N; i++) if (is_lms(sa[i])) sa[N1++] = sa[i];

        fill(sa.begin() + N1, sa.end(), -1);
        int name = 0, prev = -1;
        for (int i = 0; i<N1; i++) {
            int cur = sa[i];
            bool diff = (prev == -1);
            for (int j = 0; !diff; j++) {
                if (j>0 && is_lms(cur + j)) break;
                if (S[cur + j] != S[prev + j]) diff = true;
            }
            if (diff) name++;
            sa[N1 + cur / 2] = name - 1;
            prev = cur;
        }
        vector<int> S1, sa1(N1);
        for (int i = N1; i<N; i++) if (sa[i] >= 0) S1.push_back(sa[i]);
        if (name == N1) for (int i = 0; i<N1; i++) sa1[S1[i]] = i;
        else sa1 = SAIS(S1, name, false).sa;

        N1 = 0;
        for (int i = 0; i<N; i++) if (is_lms(i)) S1[N1++] = i;
        for (int i = 0; i<N1; i++) sa1[i] = S1[sa1[i]];

        fill(sa.begin(), sa.end(), -1);
        bucket();
        for (int i = N1; i--;) {
            int j = sa1[i];
            sa[--B[S[j]]] = j;
        }
        induced_sort();
    }
    void buildLCP() {
        rank.resize(N);
        lcp.resize(N - 1);
        for (int i = 0; i<N; i++) rank[sa[i]] = i;
        int h = 0;
        for (int i = 0; i<N - 1; i++) {
            int j = sa[rank[i] - 1];
            if (h>0) h--;
            for (; j + h<N && i + h<N && S[j + h] == S[i + h]; h++);
            lcp[rank[i] - 1] = h;
        }
    }

public:
    IRMQ<int> rmq;
    void buildRMQ() {
        rmq = IRMQ<int>(lcp.begin(), lcp.end());
    }
    int common_prefix(int x, int y) {
        if (x == y) return N - 1 - x;
        if (y >= N - 1) return 0;
        if (rank[x] > rank[y]) swap(x, y);
        return rmq.min_v(rank[x], rank[y]);
    }
    int compare(int x, int xn, int y, int yn) {
        int l = common_prefix(x, y);
        if (l >= xn || l >= yn) return xn < yn ? -1 : xn == yn ? 0 : 1;
        return rank[x] < rank[y] ? -1 : x == y ? 0 : 1;
    }
};
/*---------------------------------------------------------------------------------------------------
　　　　　　　　　　　 ∧＿∧  
　　　　　 ∧＿∧ 　（´<_｀ ）　 Welcome to My Coding Space!
　　　　 （ ´_ゝ`）　/　 ⌒i     
　　　　／　　　＼　 　  |　|     
　　　 /　　 /￣￣￣￣/　　|  
　 ＿_(__ﾆつ/　    ＿/ .| .|＿＿＿＿  
　 　　　＼/＿＿＿＿/　（u　⊃  
---------------------------------------------------------------------------------------------------*/




string S;
int N;
SAIS sais;
//---------------------------------------------------------------------------------------------------
mint memo[10101];
int vis[10101];
mint f(int L, int R) {
    if (vis[L]) return memo[L];

    mint res = 1;
    int l = L + 1, r = R - 1, n = 1;
    while (l <= r) {
        if (n <= sais.common_prefix(L, r + 1)) res += f(l, r);
        l++;
        r--;
        n++;
    }

    vis[L] = 1;
    return memo[L] = res;
}
//---------------------------------------------------------------------------------------------------
void _main() {
    cin >> S;
    N = S.length();
    
    sais.init(S);
    sais.buildRMQ();

    cout << f(0, N - 1) << endl;
}
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